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| <h3 class="section">7.54 <code>.linkonce [</code><var>type</var><code>]</code></h3> |
| |
| <p><a name="index-COMDAT-395"></a><a name="index-g_t_0040code_007blinkonce_007d-directive-396"></a><a name="index-common-sections-397"></a>Mark the current section so that the linker only includes a single copy of it. |
| This may be used to include the same section in several different object files, |
| but ensure that the linker will only include it once in the final output file. |
| The <code>.linkonce</code> pseudo-op must be used for each instance of the section. |
| Duplicate sections are detected based on the section name, so it should be |
| unique. |
| |
| <p>This directive is only supported by a few object file formats; as of this |
| writing, the only object file format which supports it is the Portable |
| Executable format used on Windows NT. |
| |
| <p>The <var>type</var> argument is optional. If specified, it must be one of the |
| following strings. For example: |
| <pre class="smallexample"> .linkonce same_size |
| </pre> |
| <p>Not all types may be supported on all object file formats. |
| |
| <dl> |
| <dt><code>discard</code><dd>Silently discard duplicate sections. This is the default. |
| |
| <br><dt><code>one_only</code><dd>Warn if there are duplicate sections, but still keep only one copy. |
| |
| <br><dt><code>same_size</code><dd>Warn if any of the duplicates have different sizes. |
| |
| <br><dt><code>same_contents</code><dd>Warn if any of the duplicates do not have exactly the same contents. |
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